Mobile communication devices generally utilize radio frequency signals for communication with remote devices such as other mobile communication devices or base stations. Modern mobile communication devices have to fulfill many requirements. Among these are multi-band operations and multi-mode operations. Modern mobile communication devices usually are able to transmit and/or receive radio frequency signals towards or from a plurality of transmitters or receivers, respectively. Especially communication devices that operate in different frequency bands in some cases comprise a plurality of different antennas in order to be operable in different frequency bands. Such communication devices may comprise rod antennas or patch antennas, like PIFAs (planar inverted F-antenna) or PILAs (planar inverted L-antenna). As antennas are radio frequency components that interact with radio frequency signals, detrimental interaction between different antennas seems generally unavoidable.
U.S. Pat. No. 7,301,502 B2 refers to an antenna arrangement that is operable in two different frequency bands but utilizes a single antenna. In order to supply the single antenna with the ability to operate in two frequency bands, an additional antenna tuning element that is located adjacent to the antenna is provided in order to improve the antenna performance with respect to operation in two different frequency bands.
However, as every antenna generally has only one frequency band around its resonance frequency with an optimal radiation efficiency, it may be preferred to utilize at least two different antennas in order to archived satisfactory antenna performance.